Establishment of a measurement method for in-shoe pressure and shear stress in specific regions for diabetic ulcer prevention.

Pressure and shear stress are the factors of diabetic foot ulcers and callus formation. However, in-shoe shear stress of callus measurement could not have been measured because of technical difficulties. The purpose of this study is to verify reliability and validity of the established measurement system for in-shoe pressure and shear stress. For reliability, coefficients of variation (CV) and intraclass correlation coefficients (ICC) were confirmed. For known-groups validity, callus and non-callus feet were compared. Mean CV was 9.7%. Mean ICC was 0.943. For validity test, mean peak pressure and shear stress of the six callus feet was significantly higher than that of the eighteen non-callus feet. The pressure and shear stress that causes callus and diabetic foot ulcer will be identified in diabetic neuropathy patients.